Universal tracing table



Jan. 12, 1965 c. PILLMORE ET AL 3,164,905

UNIVERSAL TRACING TABLE 2 Sheets-Sheet 1 Filed Aug. 16. 1961 INVENTORS CHARLES L. P/LLMORE ROBERT H. MORRIS BY J. MN

A oRNEYs Jan. 12, 1965 c. PILLMORE ETAL 3,164,905

UNIVERSAL TRACING TABLE Filed Aug. 16. 1961 2 Sheets-Sheet 2 INVENTORS CHARLES L. P/LLMORE' ROBERT H. MORRIS BY wk,

ORNEYS tables.

- .c urately measu re attitudes wherein:

. 3,164,905 M UNrvERsAL rnAcrNo TABLE. I

' Cranes L'Pilhnore, Denver, clam, and'Rohertjl-I. Morris, College of Porto Allegra, Brazil, assignors to the United- States of. America asrepresented by the Secretaryof the Interior Filed Aug. 16, 1961, Ser. No.1131fl43 6 Claims. (CL- 331-1.) (Granted under Title 35, Code (1952),sec. 266) j The invention herein described and claimed may be manufactured and used'by or for the Government or the United States of America for governmental purposes Patented Jan. .12, 1965 dipping terrain having superimposed thereon the indicator elements of the platen.

T he improved platen'andi positioning drive therefor, of

the presentinvention may be made art' ofan arrange meritv haying a conventional-tracing table frame. As

,shown in FIG. lot the drawings, arframe '15 includes a i base 'of two curved side legs 11 andl2,fjoined to form a without the payment of royalties thereon or therefor.

This invention relates to improvements in a plotting or tracing table having particular utility in photogrammetric apparatus for making contourmaps. In an apparatus suitable for this purpose, an arrangement of two stereoscopic projection devices aredirected to follow the movement of the tracing table over a surface covered by back portion 13, each part having a substantially rectaugu lar cross-section. Attached to the inside surface of the back portion 13, and centered between the-legs ll, 12, i is a'conventional writing implement 8, for marking the contour lines or other detail observed in thesstereoscopic model, on the map surface over which the tracing table may be moved. Fastened into sockets on the upper surface of portion 13, are the ends of two spaced apart and a parallel rods 14 and 15. v In a vertical planedefined by the parallel rods, and spaced between them, is anelongated drive screw. 16, rotatable in a -bearing socket in portion 13 ofthe base .510. A head bracket plate 17 a contour map, and to produce on a platen of the tracing table, a pair of overlapped images which maybe seen as a single three dimensional image by stereoscopic viewing means. A tracing stylus fixed to the tracing table is et fective to form the lines of the contour map as the table is moved about. A diagrarnmetric view of one form of this apparatus may be seen in FIG, 1 of "the US. Patent No. 2,833,178, issued to H. a". Kelsh, on Mayo, 1958.

Made possibl'e by the improvements of the present:

invention are very accurate measurements of attitudes and thicknesses of rock forrnations shown-in aerial photo- 3 graphs madein surveying the terrain of inaccessible land areas. The invention is highly effective for making meass urements of such formations in strata where the attitudes of thedips or slopes are greater than two or three degraphic means using data obtainedfrom standard; tracing By means 'of the present invention it is possible to'ae- V and thickness-of outcroppings to within two feet. 1 e I It is an object of this invention to provide a tracing table having a platen, with-a particulararrangement, of

illuminated markings to enable direct and. accurate measurements of the thickness of dippingyor sloping strata visible in the three dimensional imageprojected on the platen.

Another object is to provide supporting means for'the platenconnecting it'to-thetracingtable flfgllllBIOIlIli-il-Ilg movement relative thereto for enabling' direct and ac curate measurement of the'attitude' of dipping or sloping strata of the stereoscopic modelivisible intheirnage :pr0- jected on the platen, i t

"A. further object of the invention is to a trac- Inherent in such methods are errors in calculation-s, and line-thickness errors of graphic determinations.

grees. Formerly such measurements were obtained by 1 methods involving trigonometric calculations, or by fixed to the upper ends of 'rods 14 and 15, maintain-s their alignment, and at its center provides a bearing in which the screw .16 may turn. A knob 18 near the lower end of screw 16, is made integral therewith for turning the screw in its bearing supports. Reference may be made to FIGS. 2 and 3 of the aforementioned Kelsh-patent for a typical prior art construction of this nature.

Mounted to slide along rods 14 and 15, and tobe guided thereby, is an elevator frame 2% having appropri .ately spaced apart holes therein to accommodate the rods Also provided in elevator 20, is a threaded hole aligned in the plane defined by rods 14 and 15, and

centrally situated betweenthe spaced apart holes, to receive; drive screw 16;. As is evident from this arrangement offparts, the vertical position of elevator it) may be conveniently determined merely adjusting knob 18 to turn the 'drive screw in the .threadedhole of the elevator, A threaded block 21 equipped with a set screw 22 isrotatable on the drive screw 16, to come into, contact jwith'and bev secured to plate 17, to act in the usual man nor, as a locking'nut for the drive screw 16;.

e The improvedvmechanism by means of which are accomplished the tilt'or. dip of the tracing tableplaten and the movement of the platen normal to the plane into which it is tilted, and the elevator Ztlarejoined by a support arm 30 extending perpendicularly out of the vertical face of the elevator; Arm .30 is a. short cy lindrical element attached atone end .as an integral part .of the-elevator. At its extended-end the arm is formed ing table of rugged construction, by means of which reliable thickness dataand accurate dip{or'. -slope measurements may be obtained by using it with 'aprojection type plotter and aerial photographs, t

. Other objects and advantages of the" present invention will become more. fully apparent from the following description of a preferred embodiment of the invention, considered together. 'with the accompanying drawing FIG.';,1 is a general perspeetive view with apart cut away, of a tracing table incorporating the improvements of the present invention; a I

FIG. 2 is a; fragmentary si'ectionalpview ofthe-lplaten, its housing and supporting elements, and" pro-enac a socket-likeyopening adapted to receive. and

have secured therein by set screws, a stub end 32 of a cylindrical gear housing 31. Ajt the opposite lend of the housing, the cylindrical surface defines. a sleeve portion into which is fitted an extension 32 from a platen normal drive mechanism 60. The space enclosed within the t .gear housing 31, between the extension 39 and the inner wall of the housings stub end. 32, constitutes a gear chamber 5E0. A'cent'ered hole 33 through the. aforesaid inner wall, opens into an enlarged hole qof the stub. end.

in the outer face Details-of the platen tilt drivemechanism shown in the cut away View 'of the housing 31 in FIG. ljHalsdinchides a shaft 34,. one end. of which istight fitted'into Qacenteredhole in the end'face of-exten'sion 39 to be integral therewith, and the other end of which is supported .for rotation in; a bearing formed by hole 33 of the hous} ing 31.. Mounted 'on theshaft .34 for rotative-movement in the housing gear chamber 40, is a worm gear 35 haying I a hub thereon in contact with the end-of extension3'9,

IG-1 is aa-ss sma s re s n a i n of a t i fa f fixedto'thelshaftbya pin through the hub and shaft. i

i In a hole tl irou gh the cylindricalwalkof the housing 31 a bushingfira provides a bearing for the shaft of a -wor rn "were 9.; 37, tangentially engaged with the teeth of the worm gear 35. A knob 38 fixed to the end of the worm shaft outside. the housing facilitates the turning of the worm gearing such that shaft 34 is angularly displaced in its bearing hole 33, to turn the extension 39 in the housing sleeve and thereby tilt the platen arrangement connected thereto.- By this means the circular platen may be dipped such that an axis perpendicular through the center thereof is tilted in a plane parallel to that defined by the rods 14 and 15, from a' position vertical to the plane of the base,=to an angleof forty-five degrees in either direction.

The'disk-like member constituting the platen '41, includes a perfectly flat top surface enamelled or polished and buffed to a matte or flat finish,'and an under surface having formed thereon a raised circular rim 51,'slightly spaced from and concentric with the outer rim of the platen. Referring to FIG. 2, there is shown a recessed area on the under side of the platen, formed by the raised rim 51, which permits the platen to be slipped upon and cover a concave dish-shaped lamp housing 45. Set

screws through the raised rim contact the outer surface of housing 4-5, to secure the platen thereto. A close inspection of the platen face reveals an arrangement of small holes drilled vertically through the thickness of the platen disk. constituting this arrangment are two rows of eight evenly spaced holes 43a, and 43b, defining two straight lines intersecting at right angles over a center hole 44. To facilitate a rapid identification of the form of this pattern on a stereoscopic model, the diameter of the hole 44 at the center, is made .006 inch, the holes 43a, 4% at the outer ends of each line, are made .015 inch, and the holes 43a, 43b in between, are made .009 inch. leveled platen positions the centerhole 44 directly above the writ-' housing 46 tothe normal drive mechanism 60. As shownin FIG. 2, the housing 45 is centered and fastened on the bar 47, .such that the reflecting face of the platen 41 is parallel to this bar. Rods 48 and 49 fastened to the bar 47, and drive screw53 rotatably supported in socket t), define a plane which includes thestraight line defined by the holes 43a, 44 on the face of the platen.

A unitary rectangular bar-like structure 61 forms the hub of the normal drive mechanism 60. Thisbar-like structure may be produced by milling a-length of cylindri- I cal stock to form the rectangular block 61'as an integral part of the material forming the short cylindrical extension 39. Two centrally located spaced apart holes 62, 63, drilled vertically through milled bar 61, are adapted to receive platen guide rods 48, 49. Evenly spaced between holes 62, 63, and in the plane'defined by the guide rods, a third hole'64 is drilled to receive for rotation therein, the normal drive screw 53. At a location conveniently spaced from the upper surface of the milled bar 61, a wide rectangular slot 65 is cut to be parallel to the outer surfaces the midpoint of the slot. A disk 66 of appropriate diameter having a threaded hole through its middle, is slipped into the slot 65, to align its opening, with the hole64,

whereby the threads on the inserted drive screw 53 may be cooperatively engaged with the threads in the hole of d the disk. Serrations along the rimof disk 66 which extends out of the slot 65, facilitate the turning of the disk such that screw 53 is driven thereby to adjust the normal position of the platform-like structure to which the platen A rectangular'block portion of an upper and outer cornet of the milled bar 61, is cut away to expose a portion of the hole 62. The rod 48accommodated in this hole, is calibrated along its length to cooperated with a fiducial mark and Vernier calibrations inscribed along a vertical wall 67 of the cut-away adjacent the hole 62. A pointed element68 fastened to the extension 39 is aligned to have its indicator tip in the plane defined by rods 48, and 49.

Indicator 68 cooperates with angular'degrces calibrations inscribed across a portion of the cylindrical housing 31, adjacent the extension 39. As is obvious from the structural cooperations hereinbefore described, readings taken from the calibrations indicated by means of elements 67 and 68 represent the elevation normal to the tilted platen, and the attitude, or angle of tilt of the platen, respectively. An additional indicator may be a conventional counter device connected to be actuated by the rotation of drive screw 16. This device would be operative to indicate the relative position of elevator 20 on its supporting elements, and therefore the basic elevation of the platen carried by the elevator. An illustration of this arrangement may be found in FIG. 1 of US. Patent No. 2,740,318, to J. V.'Sharp, issued April 3, 1956. V

A 12v volt A.C. source is used in the present embodiment to supply electrical power to the bulb 42. Loosely coiled wires 9, from the bulb socket are pulled through the hollow interior of rod 14' to connect to a dimmer rheostat 7 installed on the top of the base leg 11. The

rheostat is connected to the 12 volt source by a conventional lead-in power cord. Additional small lights connected to the power cord through toggle switches on the base, may be attached near the dip indicator and platen normal vernier so that therelated scales are more easily read in darkened plotter rooms. As a further modification, the platen-and the lamp in a platen housing structure,

may be replaced by an electro-luminescent panel appropriately designed to present a platen having a proper arrangementof illuminated spots.

, of the bar. The central axis of the hole 64 passes through c is fastened. Rodsds and 49 slide in their respective holes 62 and 63 to' hold-and guide this structure in its movements.

gap in the surface 71 defining the trace 71a.

In the geologic study of a terrain, the improved tracing table of the present invention is made operative as a part of a double projection stereoscopic plotter apparatus as hereinbefore explained with reference to the patent to Kelsh. The FIG.3 representation of afragmentary stereoscopic model 70 of the terrain as viewed on the platen 41, shows a sloping or dipping terrain 71, 72, and an outcropping 73 including a distinguishing stratum 74. The bed of material forming this stratum has a dip of angle 0:, as indicated by the cross-section showing dip of the beds 75. To'find the attitude and thickness of bed 74, an initial adjustment is made by turning knob 18 to cause elevator 20 to bring the illuminated center hole 44 of a level platen to a reference point C at the upper margin or trace 71a, of the stratum. Thereafter the entire tracing table is moved about hole 44 as a center, so as to position a line 76 defined by the illuminated holes 43a on the platen, in the plane of the terrain surface 71. This may be preferably accomplished by orienting the line 76 to intersect the trace 71a-at two points of equal elevation such as shown in FIG. 3, to be at'opposite sides of the Tilt drive knob 38 is then turned to adjust the inclination of the platen41'and mechanism 60, such that the platen is inclined sufficiently to align illuminated holes 43b to the inclination of the plane defined by the points along trace 71a Thus the plane of the platen 41 (as defined by the holes 43a and 43b), is aligned parallelt'o and coincident with the plane of the dipping bed .74. A reading is now taken of the angle of'dip from the calibrated scale associated with indicator element 68. Following this, the tracing table is moved laterallyin the direction of line 76 to bringcenter hole 44 to be above the lower margin of stratum 74. A reading is made of scale 67 on rod 48. The dip' normal adjustment disk 66 is then turned to lower the platform-like structurecarrying the platen until hole .44 coincides with a point C selected on the lower margin of stratum 74. .A second reading is; taken from the scale on rod 48 as indicated by the'center mark on Vernier 67. It is evident that since all holes on line 76 are at the same elevation, this measurement may be taken without first moving the tracing table laterally, by merely turning adjusting disk 66 and noting the reading at indicator 68, when any hole 43a on line 76, coincides with the lower margin at point C. it is now evident that the reading noted at indicator 68 corresponds to the dip angle of strata 74. Also clear'is that the difference in the readings from the indicator arrangement 67 corresponds to the value of a measurement taken normal to the plane of dip, and which value when properly sealed in accordance with procedures well known in the art for this apparatus, is the thickness XY of the bed '74 of the stratum.

As will be obvious to those skilled in the art, changes and substitutions and rearrangement of parts may be made in the preferred embodiment described herein, without departing from the spirit of the invention.

We claim:

1. A tracing table having utility in adouble image,"

stereoscopic projection-contour mapping apparatus, including a base andmeans on said base supporting an elevator structure for displacement within a plane normal to said base, said elevator structure being operable for moving a platen in a straight path normal to the plane of the base, the platen having a substantially flat reflective sur-' face, the improvement comprising means connecting the platen to the elevator structure, said means comprising a platform structure to whichthe platen is fastened, and adjustable means supporting the platform structure to angularly reposition it about an axis parallel to the plane of the base and normal to said plane in whichthe elevator structure is displaceable, whereby the platen surface attached to the platform structure'is moved from a horizontal attitude to a sloping attitude, said adjustable means also operable to move the platform structure and the platen therewith in a straight path normal to the plane to said movable means and operable'for angularly displacing the supporting means, the latter comprisingadjustable means for linearly displacing said platenrelative thereto, said platen surface being provided with two rows of relatively small holes intersecting at the center of the platen, and means fastened to said holes. a

3. The tracing table and improvement of claim 1, and said platen surface being provided with'two rows of. relatively small holes intersecting at the center of the platen,

said platen to illuminate and means fastenedto 'sa'id platen to illuminate'the holes.

4. The tracing table. andimprovement of claim 3, and

said'platen surface being provided with two rows of relatively small holes intersecting at right angles over a hole at the center of the platen, and means fastenedto said platen to illuminate all said holes.

5. In the tracing table arrangement of claim 2, and the improvement comprising the platen surface thereof, the

two rows of relatively small holes being provided to intersect at right angles over a hole at the center of the I tively disposed on said base for guiding and driving said elevator structure for displacement within a plane normal to the plane of said base, a platen structure having a substantially fiat reflective surface, and further means operatively associating said elevator structure to said platen structure whereby said elevator structure is operable to move said reflective surface'in a straight path normal to the plane of said base, the improvement residing in'said further means being arranged to extend from said elevator structure and including settable means to control the dis:

placement of said reflective surface into predetermined positions, said settable means comprising a platform structure having saidplaten structure fixed thereto, a second guiding and driving means operatively connected to said platform structure to displace it in a straight path normal to the plane of said platen reflective surface, and an adjustable means joining said second'guiding and driving means to said elevator structure and operative through said juncture to displace said platform structure and the platen reflective surface therewith to different angular positions about an axis parallel to the plane of the base and normal to the plane in which saidelevator structure is displaceable.

Reterences (lited by the Examiner UNITED STATES PATENTS 1,807,999 6/31 'McMurtry 33174 1,909,923 5/33 Von Bertrab 3320 2,480,618 8/49 Tresidder 33174 2,589,824 3/52 Kuipers 33-20 2,676,409 4/54 Gamble -33-1 2,740,318 4/56 Sharp 33-20 X 2,833,178 5/58 Kelsh 33--20 X 2,871,563 2/59 Sawyer et al 33-1 FOREIGN PATENTS 597,515 1/ 48 Great Britain.

660,628 11/51 Great Britain.

ISAAC LISANN, Primary Examiner.

L. a. PRlNiDE, Examiner. 

1. A TRACING TABLE HAVING UTILITY IN A DOUBLE IMAGE STEREOSOPIC PROJECTION-CONTOUR MAPPING APPARATUS, INCLUDING A BASE AND MEANS ON SAID BASE SUPPORTING AN ELEVATOR STRUCTURE FOR DISPLACEMENT WITHIN A PLANE NORMAL TO SAID BASE, SAID ELEVATOR STRUCTURE BEING OPERABLE FOR MOVING A PLATEN IN A STRAIGHT PATH NORMAL TO THE PLANE OF THE BASE, THE PLATEN HAVING A SUBSTANTIALLY FLAT REFLECTIVE SURFACE, THE IMPROVEMNT COMPRISING MEANS CONNECTING THE PLATEN TO THE ELEVATOR STRUCTURE, SAID MEANS COMPRISING A PLATFORM STRUCTURE TO WHICH THR PLATEN IS FASTENED, AND ADJUSTABLE MEANS SUPPORTING THE PLATFORM STRUCTURE TO ANGULARLY REPOSITION IT ABOUT AN AXIS PARALLEL TO THE PLANE OF THE BASE ND NORMAL TO SAID PLANE IN WHICH THE ELEVATOR STRUCTURE IS DISPLACEABLE, WHEREBY THE PLATEN SURFACE ATTACHED TO THE PLATFORM STRUCTURE IS MOVED FROM A HORIZONTAL ATTITUDE TO A SLOPING ATTITUDE, SAID ADJUSTABLE MEANS ALSO OPERABLE TO MOE THE PLATFORM STRUCTURE AND THE PLATEN THEREWITH IN A STRAIGHT PATH NORMAL TO THE PLANE OF THE PLATEN SURFACE. 